I've found instead of having all the cards in your hand as the Marshall, its best just to use the notepad, and any cards you pick up, immediately cross off the notepad and put infront of you face up. Much easier to play.
Good idea! But I wouldn't place them face up. Part of the problem for the Fugative is they DON'T know what numbers the Marshal has. The Fugative might think they are doing a clever play by playing fake sprint cards only to find out because of the numbers the Marshal has it could only be one number.